Agency of the Subsurface

[Image: The Heathen Gate at Carnuntum, outside Vienna; photo by Geoff Manaugh.]

Last summer, a geophysicist at the University of Vienna named Immo Trinks proposed the creation of an EU-funded “International Subsurface Exploration Agency.” Modeled after NASA or the ESA, this new institute would spend its time, in his words, “looking downward instead of up.”

The group’s main goal would be archaeological: to map, and thus help preserve, sites of human settlement before they are lost to development, natural decay, climate change, and war.

Archaeologist Stefano Campana, at the University of Siena, has launched a comparable project called Sotto Siena, or “Under Siena”—abbreviated as SOS—intended to survey all accessible land in the city of Siena.

[Image: A few of Siena’s innumerable arches; photo by Geoff Manaugh.]

That project’s goal is primarily to catalog the region’s millennia of human habitation and cultural artifacts, but, like Immo Trinks and his proposed ISEA, is also serving to document modern-day infrastructure, such as pipes, utilities, sewers, and more. (When I met Campana in Siena last year, I was interested to learn that a man who had walked over to say hello, who was introduced to me as an enthusiastic supporter of Campana’s work, was actually Siena’s chief of police—it’s not just archaeologists who want to know what’s going on beneath the streets.)

I had the pleasure of tagging along with both Trinks and Campana last year as part of my Graham Foundation grant, “Invisible Cities,” and a brief write-up of that experience is now online over at WIRED.

The article begins in Siena, where I joined Campana and two technicians from the Livorno-based firm GeoStudi Astier for a multi-hour scan of parks, piazzas, and streets, using a ground-penetrating radar rig attached to a 4WD utility vehicle.

[Images: The GPR rig we rode in that day, owned and operated by GeoStudi Astier; photos by Geoff Manaugh.]

We stayed out well past midnight, at one point scanning a piazza in front of the world’s oldest bank, an experience that brought back positive memories from my days reporting A Burglar’s Guide to the City (alas, we didn’t discover a secret route into or out of the vault, but just some fountain drains).

In Vienna, meanwhile, Trinks drove me out to see an abandoned Roman frontier-city and military base called Carnuntum, near the banks of the Danube, where he walked me through apparently empty fields and meadows while narrating all the buildings and streets we were allegedly passing through—an invisible architecture mapped to extraordinary detail by a combination of ground-penetrating radar and magnetometry.

“We want to map it all—that’s the message,” Trinks explained to me. “You’re not just mapping a Roman villa. You’re not mapping an individual building. You are mapping an entire city. You are mapping an entire landscape—and beyond.”

An estimated 99% of Carnuntum remains unexcavated, which means that our knowledge of its urban layout is almost entirely mediated by electromagnetic technology. This, of course, presents all sorts of questions—about data, machine error, interpretation, and more—that were explained to me on a third leg of that trip, when I traveled to Croatia to meet Lawrence B. Conyers.

[Image: A gorge leading away behind the archaeological site I visited on the island of Brač, Croatia; photo by Geoff Manaugh.]

Conyers is an American ground-penetrating radar expert who, when we met, was spending a couple of weeks out on the island of Brač, near the city of Split. He had traveled there to scan a hilltop site, looking for the radar signatures of architectural remains, in support of a project sponsored by the University of Colorado at Boulder.

Conyers supplies a voice of caution in the WIRED piece, advising against over-relying on expensive machines for large-scale data collection if the people hoarding that data don’t necessarily know how to filter or interpret it.

[Image: Lawrence Conyers supervises two grad students using his ground-penetrating radar gear; photo by Geoff Manaugh.]

The goal of an International Subsurface Exploration Agency could rise or fall, in other words, not just on questions of funding or public support, but on the limits of software analysis and human interpretation: are we sure that what we see on the screens of our machines is actually there, underground?

When we spoke in Siena, Campana used the metaphor of a medical biopsy, insisting that archaeologists and geophysicists will always need to excavate, not just for the recovery of historical artifacts and materials, but for verifying their own hypotheses, literally testing the ground for things they think they’ve seen there.

Archaeologist Eileen Ernenwein, co-editor of the journal Archaeological Prospection, also emphasized this to me when I interviewed her for WIRED, adding a personal anecdote that has stuck with me. During her graduate thesis research, Ernenwein explained, she found magnetic evidence of severely eroded house walls at an indigenous site in New Mexico, but, after excavating to study them, realized that the structure was only visible in the electromagnetic data. It was no less physically real for only being visible magnetically—yet excavation alone would have almost certainly have missed the site altogether. She called it “the invisible house.”

In any case, many things have drawn me to this material, but the long-term electromagnetic traces of our built environment get very little discussion in architectural circles, and I would love this sort of legacy to be more prominently considered. What’s more, our cultural obsession with ruins will likely soon begin to absorb new sorts of images—such as radar blurs and magnetic signatures of invisible buildings—signaling an art historical shift in our representation of the architectural past.

For now, check out the WIRED article, if you get a chance.

(Thanks again to the Graham Foundation for Advanced Studies in the Fine Arts for supporting this research. Related: Through This Building Shines The Cosmos.)

Geomedia, or What Lies Below

[Image: Courtesy USGS.]

I love the fact that the U.S. Geological Survey had to put out a press release explaining what some people in rural Wisconsin might see in the first few weeks of January: a government helicopter flying “in a grid pattern relatively low to the ground, hundreds of feet above the surface. A sensor that resembles a large hula-hoop will be towed beneath the helicopter,” the USGS explains—but it’s not some conspiratorial super-tool, silently flipping the results of voting machines. It’s simply measuring “tiny electromagnetic signals that can be used to map features below Earth’s surface,” including “shallow bedrock and glacial sediments” in the region.

Of course, the fictional possibilities are nevertheless intriguing: government geologists looking for something buried in the agricultural muds of eastern Wisconsin, part Michael Crichton, part Stephen King; or CIA contractors, masquerading as geologists, mapping unexplained radio signals emanating from a grid of points somewhere inland from Lake Michigan; or a rogue team of federal archaeologists searching for some Lovecraftian ruin, a lost city scraped down to its foundations by the last Ice Age, etc. etc.

In any case, the use of remote-sensing tools such as these—scanning the Earth to reveal electromagnetic, gravitational, and chemical signatures indicative of mineral deposits or, as it happens, architectural ruins—is the subject of a Graham Foundation grant I received earlier this autumn. That’s a project I will be exploring and updating over the next 10 months, combining lifelong obsessions with archaeology and ruins (specifically, in this case, the art history of how we depict destroyed works of architecture) with an interest in geophysical prospecting tools borrowed from the extraction industry.

In other words, the same remote-sensing tools that allow geological prospecting crews to locate subterranean mineral deposits are increasingly being used by archaeologists today to map underground architectural ruins. Empty fields mask otherwise invisible cities. How will these technologies change the way we define and represent architectural history?

[Image: Collage, Geoff Manaugh, for “Invisible Cities: Architecture’s Geophysical Turn,” Graham Foundation 2020/2021; based on “Forum Romano, Rome, Italy,” photochrom print, courtesy U.S. Library of Congress.]

For now, I’ll just note another recent USGS press release, this one touting the agency’s year-end “Mineral Resources Program Highlights.”

Included in the tally is the “Earth MRI” initiative—which, despite the apt medical-imaging metaphor, actually stands for the “Earth Mapping Resource Initiative.” From the USGS: “When learning more about ancient rocks buried deep beneath the surface of the Earth, it may seem surprising to use futuristic technologies flown hundreds of feet in the air, but that has been central to the USGS Earth Mapping Resource Initiative.”

[Image: A geophysical survey of northwestern Arkansas, courtesy USGS.]

What lies below, whether it is mineral or architectural, is becoming accessible to surface view through advanced technical means. These new tools often reveal that, beneath even the most featureless landscapes, immensely interesting forms and structures can be hidden. Ostensibly boring mud plains can hide the eroded roots of ancient mountain chains, just as endless fields of wheat or barley can stand atop forgotten towns or lost cities without any hint of the walls and streets beneath.

The surface of the Earth is an intermediary—it is media—between us and what it disguises.

(See also, Detection Landscapes and Lost Roads of Monticello.)

Fob Jam

[Image: Unrelated photo of an Ohio suburb, via the Library of Congress, altered by BLDGBLOG].

When most of the electronic car fobs and garage door openers stopped working in an Ohio suburb, the explanation was found only by systematically mapping the town’s electromagnetic landscape.

This involved tracking down stray power signals, then turning those signals off one by one to determine which of them had been interfering with the frequencies emitted by car electronics. It was like tuning a neighborhood back to radio silence.

I’m reminded of an anecdote about experimental musician Felix Hess, as described in David Toop’s excellent book, Ocean of Sound. Requiring a performance space bothered by no “extraneous sounds,” Hess soon found that total silence was an impossible goal. There were tiny noises everywhere.

“So first we turned off the air conditioner in the room,” Toop writes in his book, “and then we turned off the one on the second floor. Then we turned off the refrigerator and the electric cooking equipment in the adjoining cafe, the power of the multi-vision in the foyer, and the power of the vending machine in a space about ten metres away. One by one we took away these continual noises, which together created a kind of drone… Hess was very interested in this and said things like, ‘From now on maybe I should do a performance of turning off sounds.’”

This town in Ohio was like a Felix Hess performance recast as a police operation.

Eventually, it led to one particular house in the neighborhood where radio signal emissions were “extraordinarily powerful.” They were coming from a kind of amateur burglar alarm, “a homemade battery-operated device designed by a local resident to alert him if someone was upstairs when he was working in his basement,” we read. “The inventor and other residents of his home had no idea that the device was wreaking havoc on the neighborhood, he said, until [local resident] Mr. Glassburn and a volunteer with expertise in radio frequencies knocked on the door.”

In any case, I love the idea of this strange, invisible world of radio signals infesting our quietest, most domestic neighborhoods, of future potential conflicts simmering amongst neighbors with the installation of every new burglar alarm, every car fob, every wireless speaker, even every cutting-edge medical implant, of gathering storms of electromagnetic contamination causing suburban garage doors to freeze in place or shudder open at 3 o’clock in the morning.

Think of the bizarre story of Hulk Hogan’s back implant that allowed him to open garage doors from a distance, but now scale that up to a domestic comedy set in a town of retirees, all of whom are amateur home-electronics tinkerers, where every day is a new electromagnetic misadventure.

Computational Landscape Architecture

[Image: An otherwise unrelated photo, via FNN/Colossal].

In 2017, researchers attending the annual Cable-Tec Expo presented a paper looking at the effect certain trees can have on wireless-signal propagation in the landscape.

In “North America in general,” the researchers wrote, “large swathes of geography are dominated by trees and other foliage which, depending on seasonal growth and longitude, can interrupt a good many LOS [line of sight] apertures between BS [a base station] and client and present performance challenges.”

That is to say, parts of North America are heavily forested enough that the landscape itself has a negative effect on signal performance, including domestic and regional WiFi.

Their presentation included a graph analyzing the effects that particular tree species—pine, spruce, maple—can have on wireless signals. “The impact of deciduous and conifer trees (under gusty wind conditions) suggest that the leaf density from the conifer more frequently produces heavy link losses and these,” they explain.

In other words, for the sake of signals, plant deciduous.

[Image: From “Can a Fixed Wireless Last 100m Connection Really Compete with a Wired Connection and Will 5G Really Enable this Opportunity?”]

What interests me here is the possibility that we might someday begin landscaping our suburbs, our corporate campuses, our urban business parks, according to which species of vegetation are less likely to block WiFi.

There is already a move toward xeriscaping, for example—or planting indigenous species tolerant of arid climates in cities such as Phoenix and Los Angeles—but what about WiFi-scaping, landscapes sown specifically for their electromagnetic-propagation effects?

One of my favorite studies of the last decade looked at whether trees planted around a fuel-storage depot in England known as Buncefield might have inadvertently caused a massive gas explosion. In this case, though, a site’s landscaping might instead cause data-propagation errors.

You can imagine, for example, vindictive foreign governments purposefully surrounding an American embassy with trees unpermissive of signal propagation, even deliberately donating specific indoor plant species known for their negative effects on electromagnetic signals. A kind of living, vegetative Faraday cage.

Hostile houseplant-gifting networks. Like the plot of some future David Cronenberg film.

[Image: Lucian Freud, “Interior in Paddington” (1951), via Tate Britain].

In any case, this brings to mind many things.

A recent study published in the MIT Technology Review, for example, suggested that WiFi could be used to spy on human movements inside architecture. The paper documents how researchers used WiFi “to work out the position, actions, and movement of individuals” inside otherwise sealed rooms.

It’s worth recalling the use of WiFi as a burglar alarm, whereby unexpected human intruders can be detected when their bodies perturb the local WiFi field. Is that someone walking toward you in the dark…? Your router might see them before you do, as their movement cause bulges and malformations in your home’s WiFi.

The more relevant implication, however, is that you could potentially use WiFi to spy on movements in the broader landscape. Deciduous forests would be easier than coniferous, it seems.

You could soak a forest in electromagnetic signals—yes, I know this is not the greatest idea—and measure those signals’ reflection to count, say, active birds, beetles, badgers, or other participants in the wilderness. It’s WiFi as a tool for ecological analysis: you set up a router and watch as its signals reverberate through the forests and fields. Animal radar.

Finally, consider a study published last year that suggested WiFi signals could be turned into a computational device. According to researchers Philipp del Hougne and Geoffroy Lerose, you can “perform analog computation with Wi-Fi waves reverberating in a room.”

Read their paper to find out more, but what seems so interesting in the present context is the idea that forested landscapes could be grown to cultivate their WiFi computational ability. Like botanical pinball machines, you could design, plant, and grow entire forests based on their ability to reflect future WiFi signals in very specific ways, artificial landscapes destined to perform computational tasks.

A bitcoin forest. WiFi forestry.

Or forest supercomputers, pruned for their ability to plumb the mathematical sublime.

(Thanks to Jameson Zimmer for the tip re: WiFI and trees. Earlier on BLDGBLOG: The Design Forest of the Sacred Grove, Forest Tone, and many others.)

Incidental Detection

[Image: Aura WiFi burglar alarm].

A new home and office alarm system detects disturbances in WiFi to warn residents of potential burglars. The Aura, as it’s known, picks up “disruptions in the invisible radio waves that make up your home’s Wi-Fi network” to determine if someone—or perhaps something—is sneaking around inside, uninvited.

When Cognitive Systems, the Canadian tech firm behind Aura, began discussing the project publicly back in 2015, they suggested that WiFi is basically an invisible shape inside your home, and that “distortions” or deformations in that shape can be detected and responded to. There is your home’s interior; then there is the electromagnetic geometry of WiFi that fills your home’s interior.

Although the alarm is capable of differentiating between an adult human being and, say, a loose piece of paper blowing down a hallway or a house plant swinging in the evening breeze, the system can apparently be thrown off by complicated architectural layouts. Perhaps, then, in the techno-supernatural future, particular homes will find themselves unavoidably haunted by nonexistent burglars, as alarms are unable to stop ringing due to an unusual arrangement of halls and closets. A new Gothic of electromagnetic effects, where the alarm is detecting the house itself.

Of course, if devices like the Aura take off, it will almost undoubtedly lead to crafty burglars developing WiFi-shape-spoofing tools as ways to camouflage their entry into, and movement through, other people’s homes. A black market economy of signal-reflection and WiFi-dazzling clothing takes off, allowing humans to move like stealth airplanes through complex electromagnetic environments, undetected. The opposite of this, perhaps.

Stories of one thing unexpectedly being used to detect the presence of another have always fascinated me. In this case, it’s just WiFi being used to pick up potential criminal trespass, but, in other examples, we’ve seen GPS satellites being repurposed as a giant dark matter detector in space. As if vast clouds of invisible matter, through which the Earth is “constantly crashing,” might set off some sort of planetary-scale burglar alarm.

[Image: GPS satellites, via MIT Technology Review].

There are so many examples of this sort of thing. Recall, for instance, that subatomic particles (or, rather, their absence) can be used to map otherwise inaccessible architectural interiors, or that an experiment in the 1930s designed “to find out what was causing the static that interfered with trans-Atlantic telephone calls” inadvertently kicked off the field of radio astronomy, or the fact that tree rings can be used to detect both sunspots and earthquakes. Or even that LIGO, the gravitational-waves detector, at one point was accidentally being set off by wolves, or that the collapse of the Twin Towers on 9/11 was picked up as an earthquake by regional seismographs.

Imagine scrambling all this; you wake up tomorrow morning to find that WiFi burglar alarms are detecting dark matter walls in space, telephone calls are picking up signs of unknown rooms and corridors hidden in the buildings all around you, and scientists outside studying wolves in the American wild have found evidence of celestial phenomena in the creatures’ tracking collars.

In fact, I’m tangentially reminded of the internet subgenre of what could be called things inadvertently captured on wildlife cameras—ghostly forms in the wilderness, lost children, “unexplained” lights. These are trail cameras that were placed there to track wildlife, either for science or for sport, but then these other things allegedly popped up, instead.

[Image: Via Outdoor Life].

I suppose this often absurd, Photoshop-prone field of purportedly occult photography comes about as close as you can to a new technological folklore, devising myths of encounter as picked up by systems originally installed to look for something else.

Yet it leaves me wondering what the “spooky trail cam” genre might produce when mixed with WiFi-enabled home burglar alarms, dark matter detectors in space, etc. etc.

In any case, the CBC has a great write-up about the Aura, if you want to learn more.

Plasma Bombs and Sky Bridges

[Image: Via NOAA].

The U.S. Department of Defense has awarded a handful of small business grants for exploring the “controlled enhancement of the ionosphere.” The aim of the grants is to find new ways “to improve radio communication over long distances”—and one of these ways might be “detonating plasma bombs in the upper atmosphere using a fleet of micro satellites,” or cubesats, New Scientist reports.

As the initiating government contract describes it, in order to perform this new atmospheric role, the cubesats—or an equally viable competitor technology—will need to produce “highly exothermic condensed phase reactions yielding temperatures considerably higher than the boiling points of candidate metal elements with residual energy to maximize their vapor yield… Such hardware will provide for controlled release options such as conventional point release, as well as extended in time and space.”

They would be, in effect, small plasma ovens—the metaphoric “bombs” of the New Scientist article.

The resulting “vapor yield” from metallic elements boiling in space would then chemically interact with the Earth’s atmosphere to create the aforementioned plasma. While spreading locally through the ionosphere, the plasma would, in turn, generate small patches of electromagnetic reflectivity across which radio signals could be bounced or relayed.

By ricocheting along this sky bridge of temporary plasma patches—like tiny chemical mirrors in space—radio signals would be able to travel far beyond the curvature of the Earth, greatly increasing the distance and accuracy of specific transmissions.

This long-range transformation of the sky itself into a transmitting medium recalls the work of radio historian Douglas Kahn. Kahn’s book Earth Sound Earth Signal specifically looks at the role of terrestrial and atmospheric dynamics on radio transmission, including the deliberate incorporation of those seemingly unwanted side-effects—such as interference from sunspot activity—into electronic art projects.

Kahn’s work came up on BLDGBLOG several years ago, for example, in discussing a proposal from the 1960s for transforming an entire Antarctic island into a radio-transmitting apparatus. The topographic profile and geologic make-up of the island made it a great potential resonator, according to researcher Millett G. Morgan.

[Image: [Image: Deception Island, from Millett G. Morgan’s September 1960 paper An Island as a Natural Very-Low-Frequency Transmitting Antenna].

By taking advantage of these physical factors—and even subtly tweaking them in what we could also call “controlled enhancement”—the island would become part of a dispersed global infrastructure of electromagnetic relay points.

It’s worth mentioning that this would also make a fascinating landscape design project: sculpting a patch of terrain, from its exposed landforms and its subsurface mineralogy to the flora planted there, such as tree-antennas, so that the whole thing becomes a kind of radio-transmitting garden.

In any case, these tactical archipelagoes of plasma dispersed across the ionosphere by military cubesats would enable emergency wartime radio contact around the planet. By introducing patches of reflectivity, they would create a temporary extension of ground-based antenna infrastructure, stretching from one side of the Earth to another, an invisible bridge in the sky put to use for planet-wide communication.

Read the original contracting information over at the Small Business Innovation Research hub.

Briefly, it’s interesting to note another piece of recent tech news. Back in April, Swati Khandelwal reported that “a team of researchers from the University of Washington’s Sensor Lab and the Delft University of Technology has developed a new gadget that doesn’t need a battery or any external power source to keep it powered; rather it works on radio waves.”

She was referring to a device called WISP, “a small, battery-less computer that works on harvested radio waves,” in the words of project researcher Przemyslaw Pawelczak.*

[Image: Przemyslaw Pawelczak’s “small, battery-less computer that works on harvested radio waves”].

This is relevant for the possibility that this sort of thing could be scaled up to much larger pieces of equipment, such as uncrewed ground vehicles or other autonomous machines (including rovers on other planets); those devices could then be deployed in the field and simply wait there, essentially hidden in a powerless state.

You could then turn on these otherwise dormant computers, even from a great distance, using only pinpointed radio transmissions assisted on their way around the planet by localized plasma clouds; like electromagnetic Frankensteins, these sleeper-systems could thus be brought back to life by this strange, military wizardry of otherwise impossible radio transmissions.

Patches of plasma appear in the sky—and machines around the world begin to awaken.

[Note: When using the appropriate Polish lettering, Przemysław Pawełczak’s name renders oddly with this blog’s typeface; it is thus deliberately misspelled in the text, above; apologies to Pawełczak. Thanks to Wayne Chambliss for his thoughts on sleeper systems while I was writing this post. Very vaguely related: Operation Deep Sleep: or, dormant robots at the bottom of the sea].

Full-Spectrum Mandala

[Image: Via the Pacific Cold War Patrol Museum].

Somewhat randomly—though I suppose I have a thing for antennas—I came across a blog post looking at the layout of Circularly Disposed Antenna Arrays.

A Circularly Disposed Antenna Array, he explains, was “sometimes referred to as a Circularly Disposed Dipole Array (CDDA)” and was “used for radio direction finding. The military used these to triangulate radio signals for radio navigation, intelligence gathering and search and rescue.”

[Image: Via the Pacific Cold War Patrol Museum].

While discussing the now-overgrown landscapes found on old military sites in Hawaii, the post’s author points out the remains of old antenna set-ups still visible in the terrain.

A series of photos, that you can find over at the original post, show how these abandoned circular land forms—like electromagnetic stone circles—exist just below the surface of the Hawaiian landscape, thanks to the archipelago’s intense militarization over the course of the 20th century.

He then cleverly juxtaposes these madala-like technical diagrams with what he calls a “Polynesian guidance system for navigating the Pacific” (bringing to mind our earlier look at large-scale weather systems in the South Pacific and how they might have guided human settlement there).

[Image: Via the Pacific Cold War Patrol Museum].

The idea that Polynesian shell map geometries and the antenna designs of Cold War-era military radio sites might inadvertently echo one another is hugely evocative, albeit purely a poetic analogy.

Finally, I couldn’t resist this brief passage, describing many of these ruined antenna sites: “Their exact Cold War era use, frequencies and purpose isn’t yet known but were most likely for aircraft radio navigation, direction finding, intelligence gathering and for search and rescue.”

You can all but picture the opening shots of a film here, as concerned military radio operators, surrounded by the arcane, talismanic geometries of antenna structures in the fading light of a Pacific summer evening, pick up the sounds of something vast and strange moving at the bottom of the sea.

The Electromagnetic Fortification of the Suburbs

[Image: A drone from DJI].

It’s hardly surprising to read that drones can be repurposed as burglars’ tools; at this point, take any activity, add a drone, and you, too, can have a news story (or Kickstarter) dedicated to the result.

“Why not send an inexpensive drone, snoop in your windows, see if you have any pets, see if you have any expensive electronics, maybe find out if you have any jewelry hanging around,” a security expert wonders aloud to Hawaii’s KITV, describing what he sees as the future of burglary. Burglars “can do all that with a drone without ever stepping a foot on your property line.”

“So what’s a homeowner to do?” the TV station asks.

They suggest following the drone back to its owner, who, due both to battery life and signal range, will be nearby; or even installing “new expensive high-tech drone detection systems that claim to detect the sounds of a drone’s propellers.” This is absurd—suggesting that some sort of drone alarm will go off at 3am, driving you out of bed—but it’s such a perfectly surreal vision of the suburbs of tomorrow.

Fortifying our homes against drone incursion will be the next bull market in security: whole subdivisions designed to thwart drone flights, marketed to potential homeowners specifically for that very reason.

You go home for the weekend to visit your parents where, rather than being enlisted to mow the lawn or clean the gutters, you’re sent you out on drone duty, installing perimeter defenses or some sort of jamming blanket, an electromagnetically-active geotextile disguised beneath the mulch. Complex nets and spiderweb-like antennas go on sale at Home Depot, perfect for snaring drone rotors and leading to an explosion in suburban bird deaths.

[Image: A drone from DJI].

This news comes simultaneously with a story in Forbes, where we read that drone manufacturer DJI is implementing a GPS block on its products: they will no longer be able to fly within 15.5 miles of the White House.

The company is issuing “a mandatory firmware update to all Phantom drones that will restrict flight within a 15.5 mile radius centered around downtown Washington D.C. Pilots looking to operate their Phantom drone will not be able to take off or fly within the no-fly-zone.”

Based off a drone’s GPS coordinates, the technology to geo-fence drones from entering a particular airspace, especially around major airports, has been around in Phantoms since early last year. The new update will add more airports to its no-fly-zone database as the 709 no-fly-zones already in the Phantom’s flight controller software will expand to more than 10,000, with additional restrictions added to prevent flight across national borders.

This is remarkable for a number of reasons, not the least of which is the fact that firmware updates and geography now work together to disable entire classes of products within a given zone or GPS range. Put another way, drones today—but what tomorrow?

Geofencing or “locationized” firearms have already been discussed as a possible future form of gun control, for example, and it would not be at all surprising to see “locationized” smartphones or geofenced cameras becoming a thing in the next few years.

All a government (or criminal syndicate) would have to do is release a (malicious) firmware update, temporarily shutting down certain types of electronics within range of, say, a presidential inauguration (or a bank heist).

[Image: A drone from DJI].

More to the point of this post, however, GPS-based geofencing will also become part of the electromagnetic armature of future residential developments, a new, invisible layer of security for those who are willing to pay for it.

Think, for example, of the extraordinary geographic dazzle effects used by government buildings to camouflage their real-world locations: as Dana Priest and William Arkin wrote for The Washington Post back in 2012, “most people don’t realize when they’re nearing the epicenter of Fort Meade’s, even when the GPS on their car dashboard suddenly begins giving incorrect directions, trapping the driver in a series of U-turns, because the government is jamming all nearby signals.”

If half the point of living in the suburbs is to obtain a certain level of privacy, personal safety, and peace of mind, then it is hardly science fiction to suggest that the electromagnetic fortification of suburbia is on the immediate horizon.

You won’t just turn on a burglar alarm with your handy smartphone app; you’ll also switch on signal-jamming networks hidden in the trees or a location-scrambling geofence camouflaged as a garden gnome at the edge of your well-mown lawn. Drones, dazzled by invisible waves of unpredictable geographic information, will perform U-turns or sudden dives, even racing off to a pre-ordained security cage where they can be pulled from the air and disabled.

The truly high-end residential developments of tomorrow will be electromagnetically fortified, impervious to drones, and, unless you’ve been invited there, impossible for your cars and cellphones even to find.

Electromagnetic Escher Mazes

The previous two posts have led to a number of interesting links, including several comments over at Reddit that seem worth reproducing here.

There, a commenter named clicksnd “used to be in a special forces Signal Detachment (as a server guy) and got awesome cross training from our radio section. One cool thing they taught us is that if we ever needed to boost range, we could wire up to a fence or, in a pinch, knife a tree and wire to it!” When you need a radio, in other words, considering just sticking some metal in a tree.

To that, someone named pavel_lishin responds: “I remember hearing a story, possibly apocryphal, about a college radio station that used some nearby railroad tracks as their broadcasting antenna, and it worked well enough for the entire town to receive the signal clearly. In fact, it worked a little too well. Someone drove up from a town a couple of hundred miles away, and asked them to knock it off, since the signal was being broadcast all the way down there and interfering with a different radio station.” Perhaps you could broadcast a radio station via all the nails in the walls of an abandoned suburb.

Finally, replying to someone mocking the idea that antennas have ever been more complex than “just a piece of metal connected to a receiver,” someone named cuddlebadger says that, on the contrary, “the field has progressed a bit since 1919,” when those tree-antennas were first being proposed. Today, cuddlebadger writes, “we have fractal antennas that look like [an] MC Escher drawing and work incredibly well. Genetic algorithms that design alien-looking antennas that are barely visible yet outperform many all-human designs. Someone even draws nanometer-scale antennas out of gold on tiny glass hemispheres for that extra efficiency. Antennas exist that can literally capture the electromagnetic radiation of sunlight!”

Electromagnetic Escher mazes made of gold, picking up emanations from stars: technology as myth achieved by other means.

Antarctic Island Radio

[Image: Deception Island, from Millett G. Morgan’s September 1960 paper An Island as a Natural Very-Low-Frequency Transmitting Antenna].

Yesterday’s post reminded me of an interesting proposal from the 1960s, in which an entire Antarctic island would be transformed into a radio-conducting antenna. Signals of international (or military submarine) origin could thus be bounced, relayed, captured, and re-transmitted using the topographical features of the island itself, and naturally occurring ionospheric radio noise could be studied.

[Image: A map of Deception Island, taken from an otherwise unrelated paper called “Upper crustal structure of Deception Island area (Bransfield Strait, Antarctica) from gravity and magnetic modelling,” published in Antarctic Science (2005)].

In the September 1960 issue of IEEE Transactions on Antennas and Propagation, radio theorist Millett G. Morgan, a “leading researcher in the field of ionospheric physics” based at Dartmouth, speculated that he could generate artificial “whistlers”—that is, audial electromagnetic effects that are usually caused by lightning—if only he could find the right island.

“In thinking about how to generate whistlers artificially,” Morgan’s proposal leisurely begins, “it has occurred to me that an island of suitable size and shape, extending through the conducting sea, may constitute a naturally resonant, VLF slot antenna of high quality.”

[Image: Deception Island, from “Upper crustal structure of Deception Island area (Bransfield Strait, Antarctica) from gravity and magnetic modelling,” Antarctic Science (2005)].

He looked far and wide for this “naturally resonant, VLF slot antenna,” eventually settling on a remote island in the Antarctic. “Following this line of reasoning,” he explains, “I thought first of the annular Pacific atolls, but knowing of the fresh-water lenses in them”—that is, aquatic features that would destructively interfere with radio transmissions—”[I] rejected them as being too pervious to water to be satisfactory insulators. Also, of course, they are not found in suitable latitudes for generating whistlers.”

Morgan’s reasoning continued: “The Pacific atolls are built upon submerged volcanic cones and this led me to think of Deception Island in the SubAntarctic, a remarkable, similarly shaped, volcanic island in which the volcanic rock extends above the surface; and which is located in the South Shetland Islands where the rate of occurrence of natural whistlers has been found to be very great.”

Perhaps the island could be the geologic radio antenna he was looking for.

[Image: Deception Island, from “Upper crustal structure of Deception Island area (Bransfield Strait, Antarctica) from gravity and magnetic modelling,” Antarctic Science (2005)].

Morgan points out in detail that mathematical ratios amongst the island’s naturally occurring landscape features, including its ring-shaped lagoon, are perfect for supporting radio transmissions (even the relationship between the length of the island and the radio wavelengths Morgan would be using seems to work out). And that’s before he looks at the material construction of the island itself, consisting of volcanic tuff, which would help the terrain act as an “insulator.”

There is even the fact that the island’s small lagoon is coincidentally but unrelatedly named “Telefon Bay” (alas, named after a ship called the Telefon, not for the island’s natural ability to make telephone calls).

[Image: Deception Island, from “Upper crustal structure of Deception Island area (Bransfield Strait, Antarctica) from gravity and magnetic modelling,” Antarctic Science (2005)].

Morgan’s “proposed island antenna” would thus be a wired-up matrix of transmission lines and natural landscape features, bouncing radio wavelengths at the perfect angle from one side to the other and concentrating broadcasts for human use and listening.

You could tune into the sky, huddling in the Antarctic cold and listening to the curling electromagnetic crackle of the ionosphere, or you could use your new radio-architectural set-up, all wires and insulators like some strange astronomical harp, “to generate whistlers artificially,” as Morgan’s initial speculation stated, bursting forth with planetary-scale arcs of noise over a frozen sea, a wizard of sound alone and self-deafened at the bottom of the world.

(Deception Island proposal discovered via Douglas Kahn, whose forthcoming book Arts of the Spectrum: In the nature of electromagnetism looks fantastic, and who also gave an interesting talk on “natural radio” a few years ago at UCLA).

Tree Receivers

[Image: “The Trees Now Talk” cover story in The Electrical Experimenter (July 1919); image via rexresearch].

Way back in 1919, in their July 14th issue, Scientific American published an article on the discovery that trees can act “as nature’s own wireless towers and antenna combined.”

General George Owen Squire, the U.S. Army’s Chief Signal Officer, made his “strange discovery,” as SciAm phrases it, while sitting in “a little portable house erected in thick woods near the edge of the District of Columbia,” listening to signals “received through an oak tree for an antenna.” This realization, that “trees—all trees, of all kinds and all heights, growing anywhere—are nature’s own wireless towers and antenna combined.”

He called this “talking through the trees.” Indeed, subsequent tests proved that, “[w]ith the remarkably sensitive amplifiers now available, it was not only possible to receive signals from all the principle [sic] European stations through a tree, but it has developed beyond a theory and to a fact that a tree is as good as any man-made aerial, regardless of the size or extent of the latter, and better in the respect that it brings to the operator’s ears far less static interference.”

Why build a radio station, in a sense, when you could simply plant a forest and wire up its trees?

[Images: From George Owen Squire’s British Patent Specification #149,917, via rexresearch].

So how does it work? Alas, you can’t just plug your headphones into a tree trunk—but it’s close. From Scientific American:

The method of getting the disturbances in potential from treetop to instrument is so simple as to be almost laughable. One climbs a tree to two-thirds of its height, drives a nail a couple of inches into the tree, hangs a wire therefrom, and attaches the wire to the receiving apparatus as if it were a regular lead-in from a lofty copper or aluminum aerial. Apparently some of the etheric disturbances passing from treetop to ground through the tree are diverted through the wire—and the thermionic tube most efficiently does the rest.

Although “40 nails apparently produce no clearer signals than half a dozen,” one tree can nonetheless “serve as a receiving station for several sets, either connected in series with the same material or from separate terminals.”

[Image: Researching the possibility that whole forests could be used as radio stations—broadcasting weather reports, news from the front lines of war, and much else besides—is described by Scientific American as performing “tree radio work.” Image via IEEE Transactions on Antennas and Propagation (January 1975)].

In a patent filing called “British Patent Specification #149,917,” Squire goes on to explore the somewhat mind-bending possibilities offered by “radio transmission and reception through the use of living vegetable organisms such as trees, plants, and the like.” He writes:

I have recently discovered that living vegetable organisms generally are adapted for transmission and reception of radio or high frequency oscillations, whether damped or undamped, with the use of a suitable counterpoise. I have further discovered that such living organisms are adapted for respectively transmitting or receiving a plurality of separate trains of radio or high frequency oscillations simultaneously, in the communication of either or both telephonic or telegraphic messages.

This research—the field of “tree radio work”—has not disappeared or been forgotten.

[Image: A tree in the Panamanian rain forest wired up as a sending-receiving antenna; from IEEE Transactions on Antennas and Propagation (January 1975)].

In the January 1975 issue of IEEE Transactions on Antennas and Propagation, we read the test results of several gentleman who went down to the rain forests of the Panama Canal Zone to test “the performance of conventional whip antennas… compared with the performance of trees utilized as antennas in conjunction with hybrid electromagnetic antenna couplers.”

The authors specifically cite Squire’s work and quote him directly: “‘It would seem that living vegetation may play a more important part in electrical phenomena than has been generally supposed… If, as indicated above in these experiments, the earth’s surface is already generously provided with efficient antennae, which we have but to utilize for communications…’ These words were written in 1904 by Major George 0. Squire, U.S. Army Signal Corps, in a report to the Department of War in connection with military maneuvers in the Pacific Division.”

The authors of the IEEE Transactions report thus establish up a jungle-radio “Test Area” in a remote corner of Panama, complete with trees wired-up as dual senders & receivers. There, they think they’ve figured out what’s occurring on a large scale, as signals propagate through the forest canopy, writing that we should consider “the jungle as a maze of aperture-coupled screen rooms. In the jungle case, the screens, in the form of vertical tree and fern trunks, and the horizontal forest canopy are of variable thickness, have variable shaped apertures, and are composed of diverse substances that contain mostly water.”

[Image: Inside the Panamanian jungle-radio Test Zone; image via IEEE Transactions on Antennas and Propagation (January 1975)].

The design implication of all this is that an ideal radio-receiving forest could be planted and maintained, complete with spatially tuned “aperture-coupled screen rooms” (trees of specific branch-density planted at specific distances from one another) to allow for the successful broadcast of messages (and/or music) through the “living vegetable organisms” that Squire wrote about in his patent application.

What other creatures—such as birds, bats, wandering children, foxes, or owls—might make of such a landscape, planted not for aesthetic or ecological reasons, but for the purpose of smoothly relaying foreign radio transmissions and encrypted spy communications, is bewildering to contemplate.

In any case, this truly alien vision of forests silently crackling inside with unexploited radio noise is incredible, implying the existence of undiscovered “broadcasts” of biological noise, humming trunk to trunk amongst groves of remote forests like arboreal whale song, inaudible to human ears, as well as suggesting a near-miraculous venue for future concerts, where music would be played not through wireless headsets or hidden speakers lodged in the woods but through the actual trees, music shimmering from root to canopy, filling trees branch and grain with symphonies, drones, rhythms, songs, sounds occasionally breaking through car radios as they speed past on roads nearby.

[All links found via an old message from Shawn Korgan posted to the Natural Radio VLF Discussion Group of which I am a non-participating member. Vaguely related: The Duplicative Forest and Pruned’s Graffiti as Tactical Urban Wireless Network. See also a follow-up post: Antarctic Island Radio].